Question

If the 17th and the 18th terms in the expansion of \((2 + a)^{50}\) are equal, then the coefficient of \(x^{35}\) in the expansion of \((a + x)^{-2}\) is:

• A. \(-35\)
• B. \(3\)
• C. \(36\)
• D. \(-36\)

Hint:

In problems involving equal terms of a binomial expansion, equating the terms helps solve for unknowns. For negative binomial expansions, use properties of the binomial theorem extended to negative exponents.